The effects of aerobic exercise on renal fibrosis and apoptosis in spontaneously hypertensive rats / 中华物理医学与康复杂志

ABSTRACT

Objective:To explore any effect of regular aerobic exercise on renal fibrosis and apoptosis in rats with spontaneous hypertension.Methods:Thirty 6-week-old male spontaneously hypertensive rats were randomly divided into a sedentary group (group HS) and an exercise group (group HE). Ten age- and sex-matched Wistar-Kyoto rats formed a control group. The rats in group HE underwent 12 weeks of swimming exercise lasting 60 minutes, five times a week, while the other two groups were kept quiet in their cages. Before and after the training, the tail artery blood pressure of each rat was measured. Renal function was evaluated after the experiment by measuring 24h urine protein, blood urea nitrogen and serum creatinine levels, while the degree of renal interstitial fibrosis was measured using Masson staining and the collagen volume fraction was calculated. The number of apoptotic cells in the renal tubular epithelial tissue was recorded by TUNEL staining and the apoptosis rate was calculated. The expression of renal transforming growth factor β1 (TGF-β1), Smad2/3, Smad7, Bax and Bcl-2 protein were detected using western blotting.Results:After the intervention, the average systolic and diastolic blood pressure and mean arterial pressure of group HS had increased significantly, while those of group HE had decreased significantly, with no significant changes in those measurements among the control group. Compared with the control group, after the intervention, the average blood pressure, 24h urinary protein, blood urea nitrogen and serum creatinine, as well as the cell apoptosis rate and expression of TGF-β1, Smad2/3 and Bax had increased significantly, and that of Smad7 and Bcl-2 had decreased significantly in group HS. And compared with group HS, in group HE the average blood pressure, 24h urinary protein, blood urea nitrogen, serum creatinine and the cell apoptosis rate had decreased significantly, together with the expression of TGF-β1, Smad2/3 and Bax, but the average expression of Smad7 and Bcl-2 had increased significantly.Conclusion:Regular aerobic exercise can relieve the renal dysfunction seen in spontaneous hypertension, at least in rats, by inhibiting renal fibrosis and apoptosis.